63658-17-3

Upstream product

• 51987-73-6 methyl 2-tert-butoxycarbonylamino-3-phenylpropanoate 
• 103999-81-1 2-Isocyanato-3-phenylpropensaeure-methylester 
• 75-65-0 tert-butyl alcohol 
• 2577-90-4 methyl (2S)-2-amino-3-phenylpropanoate 
• 52386-78-4 N-acetyl dehydrophenylalanine methyl ester 
• 55065-02-6 2-(N-acetylamino)cinnamic acid 
• 606937-27-3 Boc-(E)-ΔPhe(β-Br)-OMe 
• 606937-28-4 Boc-(Z)-ΔPhe(β-Br)-OMe 
• 1438888-29-9 C₂₀H₂₄NO₇P 
• 100-52-7 benzaldehyde 
• 1438888-28-8 C₂₈H₃₀NO₉P 
• 24424-99-5 di-tert-butyl dicarbonate 
• 121056-95-9 trimethyl 2-(tert-butoxycarbonylamino)phosphonoacetate 
• 153393-01-2 methyl 2-(bis(tert-butoxycarbonyl)amino)acetate 

Downstream Products

• 63096-29-7 Boc-α,β-Dehydrophenylalanin 
• 103999-81-1 2-Isocyanato-3-phenylpropensaeure-methylester 
• 1086602-45-0 Boc-Z-ΔPhe(β-I)-OMe 
• 51987-73-6 (S)-2-tert-butoxycarbonylamino-3-phenyl-propionic acid methyl ester 
• 19901-50-9 methyl (2R)-2-(t-butoxycarbonylamino)-3-phenylpropionate 

Relevant academic research and scientific papers

Synthesis of β-silyl α-amino acids via visible-light-mediated hydrosilylation

An expedient synthesis of β-silyl α-amino acids is reported via the application of visible-light-mediated hydrosilylation. The reaction utilizes readily accessible and structurally diverse hydrosilanes to provide radicals for conjugate addition to dehydroalanine ester and analogues. Notably, the use of chiral methyleneoxazolidinone as the substrate and chiral inducer enabled the highly stereoselective synthesis. Furthermore, the reaction could also be performed in a continuous flow fashion and scaled up to the gram scale.

Silver-Promoted Direct Phosphorylation of Bulky C(sp2)-H Bond to Build Fully Substituted β-Phosphonodehydroamino Acids

A general and practical cross-dehydrogenative coupling protocol between readily available trisubstituted α,β-dehydro α-amino carboxylic esters and H-phosphites is described. This C(sp2)-H phosphorylation reaction proceeds with absolute Z-selectivity promoted by silver salt in a radical relay manner. The bulky tetrasubstituted β-phosphonodehydroamino acids were obtained in grams and added new modules to the toolkit for peptide modifications.

Elucidation of Racemization Process of Azaspirene Skeleton in Neutral Aqueous Media

Azaspirene and related congeners, which possess various biological activities, have a unique spirocyclic core structure. However, there are few studies on the chemical properties of (-)-azaspirene, despite the fact that it may provide important insights into unveiling the biosynthetic pathway. Here, we report a nine-step chemical synthesis of an azaspirene analogue with a new finding that the natural (-)-azaspirene skeleton easily racemizes in neutral aqueous media.

CHIRAL FLUORINATING REAGENTS

This invention relates to fluorinating agents and, more particularly, to chiral non-racemic fluorinating agents useful for enantioselective fluorination, as well as to their synthesis and use and other subject matter. The fluorinating agents are based on a substituted 1,4-diazabicyclo[2.2.2]octane (DABCO) skeleton and provide electrophillic fluorine enantioselectively.

Copper-catalyzed asymmetric hydroboration of α-dehydroamino acid derivatives: Facile synthesis of chiral β-hydroxy-α-amino acids

The Cu-catalyzed asymmetric conjugate hydroboration reaction of β-substituted α-dehydroamino acid derivatives has been established, affording enantioenriched syn- and anti-β-boronate-α-amino acid derivatives with excellent combined yields (83-99%, dr ≈ 1:

Stereoselective Synthesis of (E)-α,β-dehydroamino acid esters

Dehydroamino acid (Dhaa) is recognized as a useful tool or substrate for amino acid and peptide research. Although the stereoselective synthesis of the thermodynamically more stable Z-Dhaa has been well examined and established, the stereoselective synthesis of E-Dhaa has still remained to be a challenging synthetic task. In this paper, a stereoselective synthesis of E-Dhaa esters using a new (α-diphenylphosphono)glycine is described. The characteristic aspects of the new method are summarized as follows: (i) metal additives play an important role in the promotion of E-stereoselectivities. (ii) the use of NaI was effected for the synthesis of E-Dhaas bearing an aryl substituent and an amino functionality, (iii) MgBr2·OEt2 and ZnCl 2 contributed to improve the E-stereoselective synthesis of E-Dhaas bearing an alkyl substituent and an oxygen functionality, (iv) various protecting and functional groups were compatible under the reaction conditions, and (v) N-Cbz, Boc, and acyl-α-(diphenylphosphono)glycines were served for the stereoselective olefination reaction to provide the corresponding E-Dhaas. A variety of (E)-dehydroamino acid esters were stereoselectively synthesized by using (diphenylphosphono)glycinate. The stereoselectivity was influenced by metal additives. Various (E)-dehydroamino acid esters were prepared by the condensation reaction of the new phosphonates with easily available aldehydes by choosing the appropriate reaction conditions.

Synthesis and electrochemical behaviour of β-halodehydroamino acid derivatives

Several new β,β-dihalo and β-halo-β-substituted dehydroalanines and dehydrodipeptides were synthesized by reacting the corresponding dehydroamino acid derivative with a N-halosuccinimide or in the case of β,β-di-iododehydroalanines with iodine. The results obtained confirmed that the stereochemical outcome of the halogenation reaction with β-substituted dehydroamino acids depends on the substrate. Thus, an increase Z-stereoselectivity was found when the β-phenyldehydroalanines were used as substrates and when these compounds were N-protected with 4-tolylsulfonyl or with carbamates. From this study, it is also possible to conclude that when N-iodosuccinimide was used as reagent a much higher Z-stereoselectivity is found. The electrochemical behaviour of the halogenated dehydroamino acids was studied by cyclic voltammetry. The results show a shift in the reduction peak to higher potentials of the β-halogenated dehydroamino acids when compared with the corresponding non-halogenated derivatives. As expected, the β,β-dihalodehydroalanines exhibit higher peak potentials than β-halo-β-substituted dehydroalanines and the bromo derivatives have lower peak potentials when compared with the corresponding iododehydroamino acids. Controlled potential electrolysis of several β-halo-β-substituted dehydroamino acids afforded the corresponding dehalogenated dehydroamino acids as mixtures of their E and Z-isomers. In all cases, the major isomer isolated results from dehalogenation without isomerization. These new results show that electrochemical reduction constitutes a valuable method for the synthesis of the E-isomer of β-substituted dehydroalanines. Springer-Verlag 2010.

Stereoselective syntheses of (E)-α,β-didehydroamino acid and peptide containing its residue utilizing oxazolidinone derivative

Reaction of methyl N-Boc-N-phenoxycarbonylglycinate with various aldehydes afforded the corresponding cis-4,5-oxazolidinone derivatives, which were effectively converted to (E)-α,β-didehydroamino acids by means of a base. Furthermore, N-deprotection of the oxazolidinone derivatives and subsequent coupling reaction with Boc-amino acid furnished the corresponding dipeptides, which were transformed to dipeptide containing α,α- didehydroamino acid with high E selectivity.

Michael addition of thiols, carbon nucleophiles and amines to dehydroamino acid and dehydropeptide derivatives

Michael additions of nitrogen heterocycles, thiols, carbon nucleophiles and amines to dehydroalanine derivatives, including a glycyldehydroalanine peptide, are performed in fair to good yields. Didehydroaminobutyric acid derivatives react only with the stronger nucleophiles but in considerably lower yields and often no reaction is observed with the corresponding didehydrophenylalanine derivatives. When a tosyl group is bonded to the nitrogen atom of the dehydroamino acid, in some cases the addition product undergoes elimination of this group and yields the corresponding β-substituted derivative of the α,β-didehydroamino acid. Addition of some β-dicarbonyl compounds leads to formation of products to which the structure of α,α-disubstituted cyclic amino acid derivatives is assigned.

Amino Acids, 18. - Preparation and Reactions of 2-Isocyanato-2-alkenoates

2-Isocyanato-2-alkenoates 3 were obtained in good yields by the perrhenate-catalyzed decomposition of 2-azidoalkanoates 1 in the presence of diphosgene (2a) or phosgene (2b).Methyl 2-azidopropionate (1h) reacts to give a mixture of methyl 2-isocyanato-2-p